There appears to be a major security hole in Safari 4 and 5 web browsers. A simple JavaScript code can scan autofill data and easily steal your contacts names (first and last), work place, city, state and even email addresses.

The good news:

1. It’s not possible to scan numbers; therefore, phone numbers and street addresses will not be obtained.
2. This trick does not work in Windows machines (not confirmed).
3. Vulnerability was reported to Apple more than a month ago.
4. You can prevent this from happening.Continue Reading